We introduce a new term in the glossary: RF-rack-valid keyspace.
We also highlight in our user documentation that all keyspaces
must remain RF-rack-valid throughout their lifetime, and failing
to guarantee that may result in data inconsistencies or other
issues. We base that information on our experience with materialized
views in keyspaces using tablets, even though they remain
an experimental feature.
Along with the new term, we introduce a new configuration option
called `rf_rack_valid_keyspaces`, which, when enabled, will enforce
preserving all keyspaces RF-rack-valid. That functionality will be
implemented in upcoming commits. For now, we materialize the
restriction in form of a named requirement: a function verifying
that the passed keyspace is RF-rack-valid.
The option is disabled by default. That will change once we adjust
the existing tests to the new semantics. Once that is done, the option
will first be enabled by default, and then it will be removed.
Fixesscylladb/scylladb#20356
This commit adds documentation for zero-token nodes and an explanation
of how to use them to set up an arbiter DC to prevent a quorum loss
in multi-DC deployments.
The commit adds two documents:
- The one in Architecture describes zero-token nodes.
- The other in Cluster Management explains how to use them.
We need separate documents because zero-token nodes may be used
for other purposes in the future.
In addition, the documents are cross-linked, and the link is added
to the Create a ScyllaDB Cluster - Multi Data Centers (DC) document.
Refs https://github.com/scylladb/scylladb/pull/19684
Fixes https://github.com/scylladb/scylladb/issues/20294Closesscylladb/scylladb#21348
